In a nutshell, with a −1.6%per decade change in cloud cover during 1954–2005, it becomes a climate forcing. While China is not the world, it bears consideration.

The Hockey Schtick reports:

A paper published last week finds that cloud cover over China significantly decreased during the period 1954-2005. This finding is in direct contradiction to the theory of man-made global warming which presumes that warming allegedly from CO2 ‘should’ cause an increase in water vapor and cloudiness. The authors also find the decrease in cloud cover was not related to man-made aerosols, and thus was likely a natural phenomenon, potentially a result of increased solar activity via the Svensmark theory or other mechanisms. As climatologist Dr. Roy Spencer has pointed out his book,

“The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.”

An updated analysis of cloud cover during 1954–2005 in China was performed using homogeneous cloud cover data from 314 stations. Long-term changes in frequencies of different cloud cover categories and their contributions to long-term changes in cloud cover were assessed. Furthermore, aerosol effects on cloud cover trends were discussed based on comparison of cloud cover trends in polluted and mildly polluted regions. Frequencies of clear sky (cloud cover <20%) and overcast days (cloud cover >80%) were observed to increase by ~2.2 days and decrease by ~3.3 days per decade, respectively, which accounts for ~80% of cloud cover reduction. Larger decreasing trends in cloud cover due to larger increase in clear sky frequency and larger decreases in overcast frequency were observed at stations with lower aerosol optical depth. There is no significant difference in trends regarding cloud cover, clear sky frequency, and overcast frequency between mountain and plain stations. These results are inconsistent with our expectation that larger decreasing trends in cloud cover should have been observed in regions with higher aerosol loading where more aerosols could lead to stronger obscuring effect on ground observation of cloud cover and stronger radiative effect as compared with the mildly polluted regions. Aerosol effect on decreasing cloud cover in China appear not to be supported by this analysis and therefore, further study on this issue is required.

Summary:

A homogeneous cloud cover dataset in China was used to study long-term changes in cloud cover and frequencies of cloud cover categories. A simple yet effective statistical method was applied to study quantitative contributions of graded cloud cover frequency to the overall trend in cloud cover. The relationship between AOD and cloud cover trend was analyzed to discuss aerosol effects on decadal trend of cloud cover. Major conclusions follow.

Significant decline in cloud cover with trend of −1.6%per decade during 1954–2005 was derived. Occurrences of clear sky (cloud cover <20 %) and overcast days (>80 %) were observed to increase and decline by 2.2 days per decade and 3.3 days per decade, respectively. Approximately 80% of overall trend of cloud cover is attributable to an increase in clear-sky days and a decline in overcast days.

Larger decreasing cloud-amount trends have been observed due to larger increasing clear sky frequency and larger decreasing overcast frequency at stations with lower AOD.
There is not significant difference among trends of cloud cover, clear sky frequency, and overcast sky frequency between mountain and plain stations. These analyses do not
support the speculation that the decreasing trend of cloud cover in regions with higher AOD should be larger than that in mildly polluted regions due to stronger aerosol obscuring effect on ground observation of cloud cover and stronger radiative effect in polluted regions. This suggests that causes for significant decreasing trend in cloud cover in China require further study.

90 thoughts on “Spencer’s posited 1-2% cloud cover variation found”

Solar activity was largest in the middle of the 20th century and has since basically decreased to where it is now down to what it was at the beginning of the 20th century. In spite of this, the cosmic ray intensity has not shown any trend since reliable measurements began in the early 1950s, so it would seem hard to ascribe the decrease in cloud cover to any solar variable.

Hardly surprising: pressures have been steadily rising over the Gobi Desert in China since 1960 and temperatures have been decreasing there during the same period figure 14.47 page 382 Leroux, Dynamic Analysis of Weather and Climate 2010 Springer/Praxis. This confirms once again the insightful analysis by the late French climatologist and of course shows the increase in Mobile Polar Highs reaching deeper southward, hardly a signature of global warming…

Just curious, but which measure of “solar activity” are you using to make that statement Leif? And when you state the lack of any cosmic ray trend, which measurement are you referring to? Those aren’t loaded questions, I honestly don’t know the answers and would like to be able to look at the data you are referring to. My reason for asking is because I always thought that cosmic rays were more affected by variations in the strength of the solar wind than by sunspot activity, and I wasn’t sure if there was a good dataset or set of proxies for solar wind going back that far. I also don’t know if the solar wind directly tracks sunspot activity or whether it deviates from direct correlation. With regard to cosmic ray trends, is there a long enough data set from multiple latitudes to determine if there is a difference in trend between higher and lower latitudes?

With regard to the study, I would also want to see if they ruled out large scale vegetation changes due to agricultural use changes. I remember one of the Pielke’s posting a story about the “bunny fence” in Australia and what a difference the vegetation changes made in the cloud cover on each side of the fence.

These analyses do not
support the speculation that the decreasing trend of cloud cover in regions with higher AOD should be larger than that in mildly polluted regions due to stronger aerosol obscuring effect on ground observation of cloud cover and stronger radiative effect in polluted regions.

A peculiar hypothesis. Its well established that aerosols seed clouds (and its a large effect) so one would expect higher cloud cover levels where AOD is high. I’d be surprised if the obscuring ground observation effect of aerosols was larger.

Otherwise its unfortunate that they do not relate cloud cover changes to aerosol changes. I would not make the assumption that high aerosol areas are areas where aerosol levels have increased over the period of the study. Aerosol level changes in China is a complex picture with likely decreasing particulates and black carbon, while SO2/NO2 has increased.

The aerosol picture in most of the rest of the world is very different to China. So I wouldn’t draw any global conclusions from this.

Leif Svalgaard says: April 4, 2012 at 2:40 pm
“Solar activity was largest in the middle of the 20th century and has since basically decreased”

As usually, Leif trys to mislead the readers of this blog.

The truth is that there is a debate about what the sun did during the last 50 years. There is an agreement that the sun dereased its activity from 1940-1950 to 1970. From 1970 to 2000 solar acticity is claimed by PMODto have been remained constant or slighly decreased.

However the ACRIM group claims otherwise and the solar irradiance increased from 1970 to 2000, and now is decreasing.

Leif knows very well that there exists a controversy about this issue, but he is not interested in fairly present the issues. Leif also forget to mention that PMOD composite is based on a manipulation of some satellite records. See here

The above finding about a cloud cover decreasing from 1970 to 2000 due to a 60-year astronomical/solar during its warming phase is perfectly consistent with the findings of my papers where also the cloud connection is discussed. For example

This was 2007. It has further increased or remained about the same (from what I’ve found) in the meantime. The figure is key — note the relative forcing compared to the combined GHG forcing (whatever “forcing” ultimately means in a detailed balance equation). Personally, I prefer the variation in the greybody temperature, which takes into account albedo.

To Leif:

IIRC, both the solar magnetic field and the Earth’s magnetic field fluctuate, and both affect cosmic ray counts. Polar stations e.g. Oulu do show significant increases in neutron counts since e.g. the early 80’s (~25%), do they not (which is more likely to be associated with solar fields). But as the Earth’s magnetic pole wanders and the Earth’s field fluctuates, might that not modulate cosmic ray counts as well, quite possibly in tropical regions with a differential impact on climate?

Either way, whatever the cause the Earth’s albedo appears to have significantly increased over the last 15 years. Given a baseline albedo in the ballpark of 0.3, 7% is around 0.02 variation from 1997 to the present. That corresponds to roughly 2 degrees K variation in the baseline greybody temperature before the GHE goes into effect to raise it. Note also that the decrease in albedo from 1985-1986 to 1997 almost precisely corresponds to the timeframe (and, lagged, the magnitude) of the “unexplained” temperature increase of that period, the part that was attributed to climate sensitivity on top of the GHE increase (which by itself is much smaller).

This explains — or “can” explain — why even serious climate scientists might have been mistaken about climate sensitivity. The very period where the IPCC was “stimulated” by Mann’s hockey stick in 1998 on began right at the end of a period where the albedo had dropped by 10 percent! over fifteen or twenty years, a drop that was interpreted (correctly or not) as being due to climate sensitivity — an increase in atmospheric humidity and decrease in cloud cover due to increase greenhouse forcing. According to this, however, this process should continue unabated as long as GHGs increase, leading to egregious estimates of the feedback. Note that 10% corresponds to almost 3K increased forcing all by itself (but we didn’t see all of it because it is lagged by years to decades).

However, the subsequent increase in albedo by 7% (which we can also expect to be lagged by years to decades in its effect on mean temperature) is completely unexplainable in terms of this forcing model. It directly confounds the actual physical basis of the presumed high climate sensitivity, and worse — suggests that by far the majority of the late 20th century warming was due to modulation of albedo, not modulation of CO_2.

Svensmark provides an appealing hypothesis to explain why there appears to be some connection between solar state and global temperature. However, one does not need to engage in this debate to look at the albedo data and connect it to expected global temperature. Whatever the mechanism responsible for the modulation, the modulation exists, behold it. It is not only significant, it is many times larger than the expected effect resulting from anthropogenic modulation of CO_2. It is, in fact, one of the relatively few mechanisms proposed (aside from chaos and self-organization of major heat transport mechanisms) that can explain the observed variability of global temperatures over the Holocene.

In a sane Universe, physicists and climatologists would be busting their butts to understand the 10% variability in albedo, given its primary role in thermoregulation. Instead it happens, and then everybody forgets it. It is the omitted variable — one cannot even argue that it should or shouldn’t be present, and using a constant value over decadal timescales is manifestly a mistake. Garbage in, garbage out.

Finding an explanation for this 1-2% cloud cover change will only result from application of numerous hypotheses, being tested in parallel, over some goodly periods of time. My best guess, all the likely effects in some non linear and chaotic combination.

Good for Robert Brown: Whether or not researchers adduce the cause of Earth’s “significantly increased” albedo since about 1997, the fact remains that heightened reflectivity must result in a consistent cooling trend. Cloud cover, sea-ice extent, whatever… odd indeed that legions of data-junkies simply ignore a major influence on near-term global temperature conditions.

I just finished reading it and posting on my blog, when I popped my head up and see your conversation. It’s really a pretty lame paper……. they do make a huge finding though…… the areas where clouds are in the summertime correlates well with “dampened warming”. And, it seems things get hotter without them as well!!! This study was only conducted in Eurasia…… no word about how clouds would effect the rest of the world’s summertime temps. …….

Honest question about GCR measurements….
If GCR do catalyse cloud seed formation a la Svensmark, wouldnt they subsequently fail to reach ground based measurement locations?
Put another way, if GCR’s are ‘used up’ making clouds, would that diminnish the signal recieved at ground measurement stations?

The pre-1997 decline in albedo can be explained by decreasing global anthropogenic aerosol levels (clouds seeded by them), but the post 1997 rise is something of a puzzle. A possible explanation is that while global aerosol levels were steady during this period. They increased over tropical and subtropical Asia, while decreasing at higher latitudes. Resulting in more tropical and subtropical clouds and more reflected sunlight from lower latitudes.

The theory is based on a feedback effect of +1.0 W/m2 per 1.0C increase in temperatures (signalling that cloud cover will decline by up to 5% given its net impact of -21.0 W/m2 even though humidity is expected to increase by 7.0% per 1.0C increase in temperatures and the climate modelers sometimes say they expect a 2.0% increase in cloud cover.

In reality, cloud cover is the make or break feedback effect. Humidity is based on the reasonably solid Classius Clayperon relation while cloud cover is just a guess at best.

If the cloud cover feedback is -1.0 W/m2/1.0C rather than +1.0 W/m2/C, then the CO2 sensitivity falls to 1.5C or so per doubling. The multiplier effect. Technically, I’ve always assumed this feedback effect has been tuned to deliver 3.0C per doubling since the climate models cannot actually determine what feedback clouds will deliver. +/- 1.0 W/m2/1.0C is a make or break factor. They picked 3.0C long ago and they are sticking with it.

(And humidity is not actually increasing according to the Classius Clayperon equations either. It is as flat as a board over the long term with the ENSO running its +/- level apparently).

Lief Svalguard says: …. “Solar activity was largest in the middle of the 20th century and has since basically decreased to where it is now down to what it was at the beginning of the 20th century. In spite of this, the cosmic ray intensity has not shown any trend since reliable measurements began in the early 1950s, so it would seem hard to ascribe the decrease in cloud cover to any solar variable.”

Unless you are dealing with a “threshold” system, wherein solar activity reaches a threshold at which no more significant cosmic ray can penetrate. If such, then you’d probably have to go back further than 1950, as I recall, what was it, .. cylce 19, was the peak. Looking at the Butterfly graph of sunspot area, there appears to be a near constant intensity since cycle 18 up until cycle 24. In fact, it looks pretty flat since 1940, as cycle 18 was looks to be approximately equal in magnitude to cylces 21 and 22, and to some degree, even cycle 23. The only dwarf is cycle 20. .. and of course, cycle 24.

Robert Brown wrote (April 4, 2012 at 4:36 pm): “In a sane Universe, physicists and climatologists would be busting their butts to understand the 10% variability in albedo, given its primary role in thermoregulation. Instead it happens, and then everybody forgets it. It is the omitted variable — one cannot even argue that it should or shouldn’t be present, and using a constant value over decadal timescales is manifestly a mistake. Garbage in, garbage out.”

rgb: In a sane Universe, physicists and climatologists would be busting their butts to understand the 10% variability in albedo, given its primary role in thermoregulation. Instead it happens, and then everybody forgets it. It is the omitted variable — one cannot even argue that it should or shouldn’t be present, and using a constant value over decadal timescales is manifestly a mistake.

James Sexton, from that paper: Abstract
The relationship between summer temperature, total cloud cover and precipitation over
Eurasia was investigated using observation-based products of temperature and precipitation,
and satellite-derived cloud cover and radiation products. We used a partial least squares
regression approach to separate the local influences of cloud cover and precipitation on
temperature variations. Our results suggest that the variance of summer temperature is partly
explained by changes in summer cloudiness. The summer temperature dependence on cloud
cover is strong at the high latitudes and in the middle latitude semi-humid area, while the
dependence on precipitation is strong in the Central Asia arid area and the southern Asia
humid area. During the period 1982–2009, the damped warming in extended West Siberia
accompanied with increases in cloud cover, and the pronounced warming in Europe and
Mongolia was associated with a decrease in cloud cover and precipitation. Our results suggest
that cloud cover may be the important local factor influencing the summer temperature
variation in Eurasia while precipitation plays an important role at the middle latitudes.

@TomRude “… pressures have been steadily rising over the Gobi Desert in China since 1960 and temperatures have been decreasing there during the same period … shows the increase in Mobile Polar Highs reaching deeper southward, hardly a signature of global warming…”
Didn’t know this, thanks for sharing.

James Sexton, from that paper: Abstract……….. Our results suggest that cloud cover may be the important local factor influencing the summer temperature variation in Eurasia while precipitation plays an important role at the middle latitudes.

Much more of this sort of analysis is needed.
=============================================================
While there is some good information in the paper, I’m not sure we needed someone to tell us summer temps are effected by cloud cover. From their conclusions…… “new evidence of strong damping
effects of daytime cloud cover on summer temperature.”

I suppose I should welcome their epiphanies, but it makes me want to cry at the same time. Further, when I look at this paper on clouds/temps, and look at the referred material, there is absent names I would expect on a paper about clouds. …….. “the damped warming….”…… it’s as if they wouldn’t or couldn’t say “cooling”. Again, there is some useful information in the paper, which is why I would try to direct Dr. Spencer’s attention to it………. in many ways it complements Anthony’s gem that he came across.

“This finding is in direct contradiction to the theory of man-made global warming which presumes that warming allegedly from CO2 ‘should’ cause an increase in water vapor and cloudiness. ”

Based on this ridiculous assertion alone one can only assume you didn’t bother reading the paper or perhaps you just decided to be a little bit deceitful and ignore the section that mentioned that while cloud cover decreased over China, cloud cover increased over, hang on, I’ll just cut and paste directly so there’s no mistake…”These studies have suggested total cloud cover has increased over Europe (Henderson-Sellers, 1986), Australia (Jones and Henderson-Sellers, 1992), Canada (Milewska, 2004), the United States (Sun and Groisman, 2004; Dai et al., 2006), the Former Soviet Union (Sun and Groisman, 2000), and the northern Indian Ocean (Norris, 2001).”
Hmmm, thats a fair chunk of the rest of the world.

Analysing the sensitivity of a simple two layers model (yea with two it’s enough to get a fair approximation) for three major parameters:
– For each % increase of albedo α, surface temperature will decrease by 1.0 °C.
– For each % increase of cloudiness c, surface temperature will increase by 0.5 °C.
– For each % increase of surface emissivity ε, surface temperature will decrease by 0.8 °C.

But the major challenge is to measure an average evolution of an average cloudiness over a long time line. Temperature is already difficult enough.
Interesting is also to observe how precipitations (cloud destruction) evolve in different parts of the World: http://bit.ly/HhPyOj

Last month’s flurry of the solar CMEs resulting in a 14% Forbush decrease, appears to confirm the Svensmark’s hypothesis, with a short term fall in the cloudiness approaching 7%.http://www.vukcevic.talktalk.net/Ap-Cl.htm

“Solar activity was largest in the middle of the 20th century and has since basically decreased to where it is now down to what it was at the beginning of the 20th century. In spite of this, the cosmic ray intensity has not shown any trend since reliable measurements began in the early 1950s, so it would seem hard to ascribe the decrease in cloud cover to any solar variable.”

++++++++

The demonstration of the CR effect is I think undisputed, right? No one is claiming anymore that the physics are not real.

So there remain some interesting possiblities. The cloud cover change is real and we and we have two postulates on offer: the GCM’s say the cloud cover should be increasing, it is decreasing, so they are in that single respect falsified.

The heliosphere is the diverter of GCR. You mentioned CR, not GCR. Solar CR and GCR are not the same thing. Can they be differentiated? My understanding is yes, definitely. So a simple question is whether or not there has been a fluctuation in the GCR with solar activity, and similarly has there been a fluctuation in Solar CR on the same basis.

Does the heliosphere size match the ‘solar activity’ and on what basis is this connect/disconnect made? In other words what constitutes ‘solar activity’. Basic queston I know, but just covering the bases.

It is going to be pretty tough for someone to prove that CR and GCR are not causing cloud formation as the evidence is pretty clear they do and the microphysics of cloud formation is pretty well understood. If CR and GCR hitting the Earth do not affect cloud cover and are not cyclic with solar activity, we must seek another explanation for long term changes in cloud cover.

Robert Brown says: “
To Leif:
IIRC, both the solar magnetic field and the Earth’s magnetic field fluctuate, and both affect cosmic ray counts. Polar stations e.g. Oulu do show significant increases in neutron counts since e.g. the early 80′s (~25%), do they not (which is more likely to be associated with solar fields). But as the Earth’s magnetic pole wanders and the Earth’s field fluctuates, might that not modulate cosmic ray counts as well, quite possibly in tropical regions with a differential impact on climate?
Robert – an interesting suggestion that fits with the comments and graphics of Vukcivic on this subject. These cover the fluctuating bands of plasma that follow the magnetic field lines where the magnetic and geographic equators cross – resulting from an interaction of the sub-tropical jets with the equatorial magnetic field. http://www.vukcevic.talktalk.net/LFC20.htm At places brighter spots of plasma are concentrated, most of which are associated with thunderstorms but their positions vary with GMF flux. As vukcevic states:
“As intensity of the GMF changes with time, so it will position of the magnetic Equator (and importantly) with it location of the plasma bands. One measure of this movement is the location of equatorial crossing. The equatorial crossing has moved east-wards during the last four centuries. “
My question is whether these differences in plasma concentration along the magnetic/geographic equator offer an explanation for the differences between the studies of Lindzen and Lin concerning the “iris effect” and could this be by variable modulation of cosmic rays by this plasma belt?http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdfhttp://trmm.chpc.utah.edu/paper/liuietiali2008ijgr.pdf

Mike says:
Based on this ridiculous assertion alone one can only assume you didn’t bother reading the paper or perhaps you just decided to be a little bit deceitful and ignore the section that mentioned that while cloud cover decreased over China, cloud cover increased over, hang on, I’ll just cut and paste directly so there’s no mistake…”These studies have suggested total cloud cover has increased…
=============================
You just quoted what OTHER papers have previously asserted, not what this paper asserts. It’s remarkable that some posters can complain about misunderstandings when they have in fact managed to confuse themselves.

According to the book “Canicules et glacierese – Histoire humaine ed comparèe du climat” by the French historian Emmanuel LeRoy Ladurie, during the Maunder Minimum the astronomical observations where difficult because of a persistent cloud cover, with observatories forced to work only 1 night over 3…

peter azlac says:
April 5, 2012 at 1:28 am
………….
Thanks for highlighting my effots.
Geomagnetic equator’s position is determined by magnetic strength of two poles and their geographic location. The ‘south’ pole is relatively strait forward, its strength is falling off at a steady rate and its movement is simple.
Variability in the North hemisphere is more complex; there is a bifurcation of the field with the ‘apparent pole’ wandering around, as the balance between two extremities changes. There is strong possibility that this balance is altered by impact of the geomagnetic storms due to the solar coronal mass ejections – the CMEs and not related to GCRs. http://www.vukcevic.talktalk.net/Tromso.htm result: the ‘north’ magnetic field intensity correlates well with the long term changes in the solar activity.
‘Speculative’ info at: http://www.vukcevic.talktalk.net/MF.htm

Leif Svalgaard says: April 4, 2012 at 2:40 pm
“Solar activity was largest in the middle of the 20th century and has since basically decreased”

Being economical with the actualite again Leif? Tut tut.
After we knock off your 20% From the period in the mid C20th you say was overcounted, and allow for the short, steep ramped cycles following, it’s easy to see that solar activity was cumulatively increasing above the long term average since 1749 all the way from ~1934 to ~2003.

Why you would wish to mislead by omission of important facts I can’t imagine.

The standardized method of temperature measurement (Stevenson screen) is quite sensitive to ground radiation (as readers of this site would know). One therefore needs to ask the question; would the same temperature rise be evident if the measurements were taken higher above the ground? (ie 10 or 20m). I am not implying that there’s no connection between CC and LT temperature, merely pointing out the limitations of ground based measurements.

As early as the 1950s deforestation in China attracted attention, but it was not until the 1960s that it assumed alarming proportions.http://tinyurl.com/cpkx6de

Could desiccation be another?

North and northwest China, where the average annual precipitation has decreased by one third between the 1950s and the 1980s,2 has been experiencing just such a desiccation process. Evidence is clear and abundant. For example, lake Lobnor vanished in 1972, and lake Kukunor, since the beginning of Holocene period, has dwindled in area by one third and in depth by 100 m.3 Finally, the depth of lake Ohlin, at the head of the Yellow River, has been dropping by over 2 cm annually.4http://www.library.utoronto.ca/pcs/state/chinaeco/forest.htm

Here is a model based on IPCC assumptions that states that China should expect more floods.

The significant increases of heavy rainfall ratios indicate that as the climate warms, heavy rainfall events are expected to increase at rates that are much faster than increases in total precipitation amounts, indicating that China will experience increased amounts of flooding. These results are substantially consistent among the three IPCC (Intergovernmental Panel on Climate Change) scenarios.

The increased probability of heavy rainfall events in China is closely connected with increased transportation of water vapour from the Arabian Sea and the South China Sea. Additionally, atmosphere stratification has become increasingly unstable, which has provided a favorable background for the initiation of heavy rainfall at the end of the 21st century.http://onlinelibrary.wiley.com/doi/10.1002/joc.2278/abstract

So if Cloud Cover is decreasing, and the trend is statistically significant, couldn’t this verify the ACRIM composite which shows a statistically significant trend upward between Solar Cycle minimas over the last 30 years?

Tom_R says:
April 4, 2012 at 9:47 pmLeif, IIRC, it was only one class of cosmic radiation that was supposed to promote cloud formation. Does the neutron monitor discriminate between different types of cosmic rays?
No, but the Earth’s magnetic field does: The low energy GCRs that are not supposed to be active do not reach lower latitudes. The high-energy GCRs are much less modulated by solar activity.

Crispin in Johannesburg says:
April 5, 2012 at 12:58 amThe demonstration of the CR effect is I think undisputed, right? No one is claiming anymore that the physics are not real.
The efficiency of the process seems much too low to have any effect. More importantly, the claimed correlations do not hold up.

The heliosphere is the diverter of GCR. You mentioned CR, not GCR. Solar CR and GCR are not the same thing.
When speaking about cosmic rays one always mean the galactic ones. The solar ones are called Solar Energetic Particles and are of much lower energy and abundance [thus should have no climate effect].

Does the heliosphere size match the ‘solar activity’ and on what basis is this connect/disconnect made? In other words what constitutes ‘solar activity’.
Short answer is ‘yes’. Solar activity is the occurrence of magnetic fields and their various side effects.

It is going to be pretty tough for someone to prove that CR and GCR are not causing cloud formation as the evidence is pretty clear they do
That is wishful thinking. The evidence is too weak to be taken seriously.

peter azlac says:
April 5, 2012 at 1:28 amBut as the Earth’s magnetic pole wanders and the Earth’s field fluctuates, might that not modulate cosmic ray counts as well, quite possibly in tropical regions with a differential impact on climate?
Yes, and that modulation is much larger than the solar modulation.

As vukcevic states:
Most of what he says is pure nonsense. [and he is proud of it…]

tallbloke says:
April 5, 2012 at 2:41 amit’s easy to see that solar activity was cumulatively increasing above the long term average since 1749 all the way from ~1934 to ~2003.
Slide 2 of http://www.leif.org/research/SHINE-2011-The-Forgotten-Sun.pdf shows solar activity since 1840 [sunspot number, geomagnetic activity, and the magnetic field in the Heliosphere]. As you can see, activity was low broadly around 1900 and 2010 and high in between. If the Sun modulates climate in any significant way, the climate now should resemble that of the early 1900s. Does it?

I’ve had a look at hours of sun records from two data sets, in Hungary (a continental climate) and the UK (a maritime climate) and solar exposure from Australia. In all cases the units they measure, hours of sun or solar exposure, are inversely related to cloudiness.

The Hugarian data show that average daily hours of sun increased 0.02 hours a day, relative an average of 5.3 hours, over the period 1970 to 2000. The Australian data show that solar exposure increased by 0.45 MJm-2year-1 relative to an average of 17.9 MJm-2. The UK data are most interesting. They show that in the period up 1966, when temperatures were falling, hours of sun fell 0.04 hours/year. In the period up to 2000, when temperatures were rising, they increased at the same rate.

The decrease in Cloud Cover that this new paper found is even more dramatic than Dr. Spencer’s 1-2% variations in Cloud Cover figure. It finds a decrease in Cloud Cover that is -1.6% PER DECADE for about 5 decades, which suggests that Cloud Cover may have an even larger role on Climate Change than even Dr. Spencer suggests, taking this study verbatim.

This could have significant implications for Climate Change, if the study’s results are to be correct.

Snowlover123 says:
April 5, 2012 at 5:52 amSo if Cloud Cover is decreasing, and the trend is statistically significant, couldn’t this verify the ACRIM composite which shows a statistically significant trend upward between Solar Cycle minimas over the last 30 years?
You are putting the cart in front of the horse here. There is no such trend.

Leif Svalgaard says: As you can see, activity was low broadly around 1900 and 2010 and high in between. If the Sun modulates climate in any significant way, the climate now should resemble that of the early 1900s. Does it?

And according to this chart, there were several low solar cycles leading up to and after the 1900s http://solarscience.msfc.nasa.gov/images/bfly.gif So why pick the one in the middle to use as your proof? If you take a boiling pot off the heat, it doesn’t immediately go cold. Sheesh. I don’t understand why you just cant admit that you really haven’t seen everything the sun is going to throw at us and as far as your science goes, its still an infant when compared with the sun’s history. What about the new studies showing that solar activity adds a lot of energy into the upper atmosphere. Wheres your chart of that? I respect you sir, but sometimes your hubris just kills me.

Leif Svalgaard says:
April 5, 2012 at 6:10 am
“Slide 2 of http://www.leif.org/research/SHINE-2011-The-Forgotten-Sun.pdf shows solar activity since 1840 [sunspot number, geomagnetic activity, and the magnetic field in the Heliosphere]. As you can see, activity was low broadly around 1900 and 2010 and high in between. If the Sun modulates climate in any significant way, the climate now should resemble that of the early 1900s. Does it?”

Leif,
I do not know if you agree that there have been long term (order of 1000 Y or so) varying trends, which include the medieval warm period, little ice age, and present warm period. You should, as data is strongly supporting this. The level of the present warm period is the order of if not cooler than the MWP. Why do you insist that shorter trends due to causes such as solar variation, superimposed on longer trends (for whatever their cause) need to agree in absolute level? They are riding on the longer term trend, so different times have different reference levels. Why do you think the level of early 1900’s should be a factor in the 2010 period if the recovery from the obviously unusual LIA gives a trend that extended the full 20th C? If you now examine recent trends in temperature, you may note the recent warm period has leveled off and likely will tend down from here.

pkatt says:
April 5, 2012 at 7:32 amArent you the same guy who has been telling us for months that this solar cycle more closely resembled minima 1954
Not at all. You have the year wrong. Compare the current cycle to cycle 14: http://www.leif.org/research/SC14-and-24.png

If the Sun modulates climate in any significant way, the climate now should resemble that of the early 1900s. Does it?

Or rather, since the Ocean is a buffer with timescales that are decades to centuries long, the climate should barely have started changing back to what it looked like in the late 1800s. And perhaps it has. We won’t know for sure for up to 1-3 more solar cycles, will we?

It’s not like temperatures instantly spiked up in association with solar state, is it? Decadal lapses, or even longer, are absolutely to be expected when the small variations in net insolation have to heat up a kilometer or so of the ocean that covers 70% of the planet to make a significant secular change in average temperature.

pkatt says:
April 5, 2012 at 7:32 amSheesh. I don’t understand why you just cant admit that you really haven’t seen everything the sun is going to throw at us and as far as your science goes, its still an infant when compared with the sun’s history.
But you think that everybody else has?

What about the new studies showing that solar activity adds a lot of energy into the upper atmosphere. Wheres your chart of that?
On slide 9 of http://www.leif.org/research/POES%20Power%20and%20IHV.pdf
And that energy is extremely small [like 1000 trillion times smaller] compared to the ordinary heat and light that gets to the lower atmosphere where you live.

In a nutshell, with a −1.6%per decade change in cloud cover during 1954–2005, it becomes a climate forcing. While China is not the world, it bears consideration.

The cited paper actually talks about cloudiness in the rest of the world. It’s suprising that this section hasn’t been quoted seeing as it is germane to the implications being made here and at The Hockey Schtick.

Many prior studies have analyzed ground-based cloud cover data from particular countries or regions for variations in cloud cover, and some studies have been conducted regarding cloud-type variation. These studies have suggested total cloud cover has increased over Europe (Henderson-Sellers, 1986), Australia (Jones and Henderson-Sellers, 1992), Canada (Milewska, 2004), the United States (Sun and Groisman, 2004; Dai et al., 2006), the Former Soviet Union (Sun and Groisman, 2000), and the northern Indian Ocean (Norris, 2001). In contrast, a decreasing trend in the annual-mean total cloud cover has been revealed over much of China during 1954–1996 (Kaiser, 2000) and 1954–2005 (Xia, 2010a).

While projections of global trends indicate more cloudiness and water vapour, it is also projected that some areas will become drier and some wetter.

If the Sun modulates climate in any significant way, the climate now should resemble that of the early 1900s.

Absolute nonsense. That is like saying that if day length modulates climate in any significant way, then March temperatures should resemble those of September. It isn’t just (one of the many) instantaneous inputs to the system that define a system’s state, it is also the initial conditions.

Leif understands this. For him to make these silly arguments belies a distinct lack of … well, lets just leave it at “objectivity.”

Robert Brown says:
April 5, 2012 at 8:06 amAnd perhaps it has. We won’t know for sure for up to 1-3 more solar cycles, will we?
I don’t see people pushing the Svensmark idea dealing with decade/centuries long time lags. Perhaps you could show me some? Now, the main modulator of cosmic rays is the geomagnetic field which has decreased 15% the past 150 years. This should have increased the GCR flux during that time, with a cooling as the result. Has the climate cooled the past 150 years? Or perhaps the time lag is longer, maybe 1000 years or more. Maybe the GCRs that are active have so high energy that they are not modulated by the Earth’s field, but then they are also not modulated by the Sun, or perhaps one need some special pleading: the GCRs are JUST energetic to be solar modulated, but JUST not enough to be modulated by the Earth.

Robert Brown says:
April 5, 2012 at 8:06 amthe climate should barely have started changing back to what it looked like in the late 1800s.
And in the late 1800s it had barely started changing back to what it looked like in the late 1700s at which time it had just barely started changing back to what it looked like in the late 1600s, at which time it had barely…

JJ says:
April 5, 2012 at 9:39 amThat is like saying that if day length modulates climate in any significant way, then March temperatures should resemble those of September.
And they do, more than they resemble those of December and those of June. Now, don’t get confused about the time scales: climate is a many-year average, not on a month scale, but that is perhaps too silly for you.

You are putting the cart in front of the horse here. There is no such trend.
slides 31 and 33:
“Observed data do not support a measureable TSI trend between the minima in 1996 and 2008 !”
———————————————————————–
That’s interesting, considering the new paper stops in 2005, and you have data continuing all the way to 2008, to try and somehow disprove the data that ended in 2005.

Snowlover123 says:
April 5, 2012 at 10:30 am“Observed data do not support a measurable TSI trend between the minima in 1996 and 2008 !”
That’s interesting, considering the new paper stops in 2005, and you have data continuing all the way to 2008, to try and somehow disprove the data that ended in 2005.
Snowlover123 says:
April 5, 2012 at 5:52 am
ACRIM composite which shows a statistically significant trend upward between Solar Cycle minimas over the last 30 years?

In my book, the ‘last 30 years’ include 2008.

Snowlover123 says:
April 5, 2012 at 10:34 amI take it you haven’t read Morvdinov and Willson 2003, (http://pubs.giss.nasa.gov/docs/2003/2003_Willson_Mordvinov.pdf) which found a statistically significant trend upward in TSI between the minimas of SC 21 and 22 from the ACRIM TSI composite?
Of course I have, but that is probably an instrumental fluke as ACRIM TSI was down again in 2008. To reiterate: “there is no observational evidence for any persistent trend in TSI at mimina.

Snowlover123 says:
April 5, 2012 at 10:36 amThe new paper’s Cloud data stops in 2005, and you have TSI data going all the way to 2008 to somehow disprove the solar connection with the Cloud Cover decrease.
No, I have solar data going all the way back three hundred years showing no convincing solar connection with climate. Now, you may want to respond to people who claim that there is a decade/century long time lag between the sun and climate. Or are you one of those who believe there is no lag?

What is the process that causes the estimated 11 year sun spot cycle?
Lately I’ve been looking at the positions of the outer planets in relation to sun spot minimum and sun spot maximum (just out of interest) I’m currently working on the math, but I have noticed that there is or appears to be a cycle of about 11 years related to the total planetary mass of Jupiter, Saturn, Uranus and Neptune and their periodic solar distribution. Like I said, I’m only studying this out of interest and I haven’t completed the math yet but what I’ve seen is very interesting, where it appears to take Roughly 11 years for the outer planets to become evenly balanced to becoming unevenly balanced, and there are various configurations of this that seem to coincide with lower or higher sun spot activity. A good way I can think of explaining this is that the outer planets are behaving like a giant weights sitting on a giant scale and the sun is the pivotal point, the scale moves up and down every 11 or so years and depending on the configuration of the weights the scales can tip higher or lower. It’ll take a further month or two for me to finish my study on this. I thought that the solar buffs here might have a thought on this.

The alternative idea as condensed in herehttp://www.vukcevic.talktalk.net/GTCa.htm
will get some traction when all the alternatives are thoroughly and systematically trashed by experts from the opposing camps.

Of course I have, but that is probably an instrumental fluke as ACRIM TSI was down again in 2008. To reiterate: “there is no observational evidence for any persistent trend in TSI at mimina.
———————————————————————–

How do you know it’s a fluke other than the fact that TSI went down at the next Solar Minimum? How can you explain Fall et. al 2011’s finding that at the best sited weather stations there is no diurnal trend, while temperature anomalies climbed? How can you account for the fact that Clouds are decreasing? How can you account for the fact that more TSI is reaching Earth’s Surface?

There are a lot of variables that point to the ACRIM composite being more accurate than the PMOD composite.

Leif says… No, I have solar data going all the way back three hundred years showing no convincing solar connection with climate.
————————————————————–

That’s interesting, considering the sun is the reason why the temperature rises during the day, and it is the energy supply of everything on Earth, so I would assume it would have something to do with the climate of Earth.

Sparks says:
April 5, 2012 at 11:14 am
………….
“Something like this
That word is BANNED on the WUWT don’t you know?”

vukcevic I suppose that forbidden word has it’s roll to play too, I was studying the mass vs Planetary positioning on sun spot number, the math at this stage adds up, It’s not a million miles away tho. We have to find out these things for ourselves I guess, This is why I never worry about how dumb my questions appear to be. I’m actually took a bit more seriously outside of the blogosphere. :)

According to William Gray, PhD, Professor Emeritus of Atmospheric Sciences, CSU:

“GCMs assume that an increase in atmospheric CO2 will cause weak global warming and an
increase in global precipitation that will lead to a large increase in upper-level water vapor
and cloudiness. They simulate that this increase in water vapor and cloudiness will block
large amounts of infrared radiation emitted to space. New observations by satellite and
reanalysis data, however, do not support these GCM assumptions. The global warming that
has occurred since the mid-1970s has been associated with a modest decrease of global
upper tropospheric water vapor and an increase of Outgoing Longwave Radiation (OLR).
These measurements contradict model predictions.”

If you argue that Uranus has characteristics peculiar to it that may account for the temperature change, would that not also apply to the other planets? Or perhaps the sun is selective about which planets it will warm?

It is curious that while discussion rages about the quality of Earth’s climate monitoring system with its milions of temperature measurements from various sources, you imply some kind of certainty about the temperature trends of other planets, for which the data is many orders of magnitude more sparse – some studies relying on less than ten data points.

It also occurs to me that the people expressing the most certainty about AGW and related science are the critics. What’s your confidence interval on Mars warming? You base your understanding on an article at the website of ‘The Search for Extraterrestrial Intelligence’? Hmmmm.

Basically what I have suggested is in line with procedures used In detecting extrasolar planets orbiting stars. Anyone who believes that planets do not have an effect on the star they orbit are missing out on a lot of progress made recently in astronomy. At the moment I do think that the solar cycle is caused by the outer planets orbiting the sun, I think the math is there, I think the suns variability does indeed have an effect on the earths temperature. And more importantly I think that it would be a useful tool for meteorologists to understand this process and tie this Solar cycle down.
Even the fact that the term ‘solar cycle’ should be a clue to it’s mathematical nature, The heliocentric configuration of the outer planets are causing the solar cycle, when the solar cycle is high over successive decades this produces overall a higher energy budget reaching the inner planets. And when the solar cycle is lower over successive decades it produces a lower overall energy budget reaching the inner planets. the interesting thing about the outer planets is that we can very accurately predict their future positions and therefor will be able to predict future heliocentric configuration and it’s effect on the sun. it means the solar cycle can be predicted with incredible accuracy decades into the future. wouldn’t this be important?

Some so-called scientists need to put down that latest book they’re promoting and do some work.

As a purely mathematic exercise, the ‘harmonics’ of orbital patterns throughout the solar system offer so much variety that there will probably be more than one set of frequencies that fit with the solar cycle/s. How would you distinguish the *true* frequencies from other candidates?

Your Mars link is broken, but is the same paper referred to in my post which found “rise in the Martian global temperature over the past 20 years. The rise, less than 2° for both surface and air temperature, is still significant from a geologic perspective” This is a non-seasonal change

The most recent of the two Neptune articles suggests a non-seasonal change in solar activity is responsible for warming

The Triton article states global warming has occurred since 1989 and that observations are the opposite of what would be expected for a seasonal change.

The Jupiter link notes climate change with no mention of seasonal influence.

In sum, you have done a great job disproving your claim, “Studies of climate changes on other planets/moons almost universally conclude seasonal variation is the cause, rather than solar variation.”

“As a purely [mathematical] exercise, the ‘harmonics’ of orbital patterns throughout the solar system offer so much variety”

barry, This is called eccentricity! where The orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle. It is also a measurable mathematical property. I wouldn’t go down the road of statistically Analysing planetary orbital deviations.(and it is not what I was suggesting)

“…that there will probably be more than one set of frequencies that fit with the solar cycle/s. How would you distinguish the *true* frequencies from other candidates?”

I would begin by observing the heliocentric configuration of the outer planetary orbital mass. I don’t understand what ‘frequencies’ you are referring to or in what context you mean.

The authors investigate a model of albedo changes from Martian dust storms causing changes in climate. Their hypothesis is that internal wind/dust/albedo feedbacks are responsible for large climate variations. It is a very tentative hypothesis, based mostly on two data points – albedo composites twenty years apart. A lot of assumption goes into the modeling. They also note:

In addition, predicted increases in summertime air temperatures at high southern latitudes would contribute to the rapid and steady scarp retreat that has been observed in the south polar residual ice for the past four Mars years

At no time do they suggest the presumed climatic change is driven by solar variation (which, at any rate, appears to have exhibited little to no trend for the last 50 – 60 years).

The Triton paper posits changed insolation from orbital dynamics – not increased solar radiation – could be responsible for apparent atmospheric pressure increase and subsequent warming. The authors at no time suggest solar variance is responsible. Orbital variations on decadal time scales are ‘seasonal’ in nature (rather than geologic).

The Jupiter paper does not posit ‘seasonal’ climate change. It posits climate change from processes internal to the planet, not solar variation.

None of these papers (except the last one I observed in my post) posit solar variation as causing climate change.